It is known to form metal ohmic contacts by depositing a metal, such as nickel, and annealing the metal at a high temperature (such as temperatures greater than 900° C.). High temperature annealing may damage epitaxial layers of gallium nitride based materials included on the SiC substrate. Accordingly, there is a need for improved methods for forming ohmic contacts to substrates of materials such as SiC, GaN, InGaN or the like.
It is also known to form metal ohmic contacts by annealing a metal layer on a substrate using a laser. Such an approach is described in, for example, U.S. Patent Application Publication No. 2005/0104072 by Slater, Jr. et al.